A mysterious shooting takes place in Seoul. As a result, Han-kyu Lee (Song Kang-ho) released by the South Korean secret service.
Six years later he sees Ji-won Song (Dong-won Kang), the North Korean spy who is partly responsible for his dismissal.
This is already his country abandoned and is now trying to conceal his identity. First run both a bit around each other,
but they soon find they need each other and complement each other.